5.1 This standard classifies soils from any geographic location into categories representing the results of prescribed laboratory tests to determine the particle-size characteristics, the liquid limit, and the plasticity index.5.2 The assigning of a group name and symbol(s) along with the descriptive information required in Practice D2488 can be used to describe a soil to aid in the evaluation of its significant properties for engineering use.5.3 The various groupings of this classification system have been devised to correlate in a general way with the engineering behavior of soils. This standard provides a useful first step in any field or laboratory investigation for geotechnical engineering purposes.5.4 This standard may also be used as an aid in training personnel in the use of Practice D2488.5.5 This standard may be used in combination with Practice D4083 when working with frozen soils.NOTE 5: Notwithstanding the statements on precision and bias contained in this standard: The precision of this test method is dependent on the competence of the personnel performing it and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of this test method are cautioned that compliance with Practice D3740 does not in itself assure reliable testing. Reliable testing depends on several factors; Practice D3740 provides a means for evaluating some of those factors.1.1 This practice describes a system for classifying mineral and organo-mineral soils for engineering purposes based on laboratory determination of particle-size characteristics, liquid limit, and plasticity index and shall be used when precise classification is required.NOTE 1: Use of this standard will result in a single classification group symbol and group name except when a soil contains 5 to 12 % fines or when the plot of the liquid limit and plasticity index values falls into the crosshatched area of the plasticity chart. In these two cases, a dual symbol is used, for example, GP-GM, CL-ML. When the laboratory test results indicate that the soil is close to another soil classification group, the borderline condition can be indicated with two symbols separated by a slash. The first symbol should be the one based on this standard, for example, CL/CH, GM/SM, SC/CL. Borderline symbols are particularly useful when the liquid limit value of clayey soils is close to 50. These soils can have expansive characteristics and the use of a borderline symbol (CL/CH, CH/CL) will alert the user of the assigned classifications of expansive potential.1.2 The group symbol portion of this system is based on laboratory tests performed on the portion of a soil sample passing the 3-in. (75-mm) sieve (see Specification E11).1.3 As a classification system, this standard is limited to naturally occurring soils.NOTE 2: The group names and symbols used in this test method may be used as a descriptive system applied to such materials as shale, claystone, shells, crushed rock, etc. See Appendix X2.1.4 This standard is for qualitative application only.NOTE 3: When quantitative information is required for detailed designs of important structures, this test method must be supplemented by laboratory tests or other quantitative data to determine performance characteristics under expected field conditions.1.5 This standard is the ASTM version of the Unified Soil Classification System. The basis for the classification scheme is the Airfield Classification System developed by A. Casagrande in the early 1940s.2 It became known as the Unified Soil Classification System when several U.S. Government Agencies adopted a modified version of the Airfield System in 1952.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This practice utilizes symbols to depict security systems and equipment requirements for architectural or engineering drawings that are produced either manually or by computer aided design (CAD). The symbols depicted include some symbols that have already been somewhat universally accepted or that have already been adopted by a standards-writing body. Generic symbols of a class of security device may be sufficient in some instances. Moreover, the need to provide a measure of security in the actual drawing may also suggest a need to utilize a generic symbol rather than to depict the exact device being installed. In the event that a greater level of detail is required, it is possible to combine many of the symbols to create new symbols that achieve the desired level. While some combinations of symbols are shown, it would be impractical to attempt to depict every conceivable combination of symbols.1.1 This practice utilizes symbols to depict security systems and equipment requirements for architectural or engineering drawings that are produced either manually or by computer aided design (CAD). The symbols depicted include some symbols that have already been somewhat universally accepted or that have already been adopted by a standards-writing body, such as by the National Fire Protection Association.1.2 It is not proposed that all of the symbols need to be utilized since the level of detail required for drawings is likely to vary. Generic symbols of a class of security device may be sufficient in some instances. Moreover, the need to provide a measure of security in the actual drawing may also suggest a need to utilize a generic symbol rather than to depict the exact device being installed.1.3 In the event that a greater level of detail is required, it is possible to combine many of the symbols to create new symbols that achieve the desired level. While some combinations of symbols are shown, it would be impractical to attempt to depict every conceivable combination of symbols. It is also the intent of this practice that the symbols be capable of being continuously expanded and modified as the industry state of the art changes or as emphasis varies. For example, little attention is given to document security in the security symbols since such requirements are not generally fully met during construction periods but are rather developed and provided for subsequently. Since much of this equipment is not installed but is “placed,” such as furniture, there is only one symbol proposed (for example, for document shredders).1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Use of this practice may increase performance in one or more areas including: cost control; resource allocation; schedule management; quality control; risk management; or safety. Perform VE/VA as early as possible in the life cycle of the focus of study, and anytime conditions change, to allow greatest flexibility and effectiveness of any recommended changes. However, VE/VA may be performed at any time during the planning, design, and implementation phases of a project, product, or process.5.2 Most effective applications of VE/VA are early in the design phase. Changes or redirection in the design can be accommodated without extensive redesign at this point, thereby saving the owner/user/stakeholder's time and money.5.3 Projects Related to the Construction of Buildings and Other Engineered Systems: 5.3.1 During the earliest stages of design, refer to VE/VA as value planning. Use the procedure to analyze predesign documents, for example, program documents and space planning documents. At the predesign stage, perform VE/VA to define the project's functions, and to achieve consensus on the project's direction and approach by the project team, for example, the owner, the design professional,5 the user, and the construction manager. By participating in this early VE/VA exercise, members of the project team communicate their needs to the other team members and identify those needs in the common language of functions. By expressing the project in these terms early in the design process, the project team minimizes miscommunication and redesign, which are costly in both labor expenditures and schedule delays.5.3.2 Also perform VE/VA during schematic design (up to 15 % design completion), design development (up to 45 % design completion), and construction documents (up to 100 % design completion). Conduct VE/VA studies at several stages of design completion to define or confirm project functions, to verify technical and management approaches, to analyze selection of equipment and materials, and to assess the project's economics and technical feasibility. Perform VE/VA studies concurrently with the user/owner's design review schedules to maintain the project schedule. Through the schematic design and design development stages, the VE/VA team analyzes the drawings and specifications from each technical discipline. During the construction documents stage, the VE/VA team analyzes the design drawings and specifications, as well as the details, and equipment selection, which are more clearly defined at this later stage.5.3.3 A VE/VA study performed at a 90 to 100 % design completion stage, just prior to bidding, concentrates on economics and technical feasibility. Consider methods of construction, phasing of construction, and procurement. The goals at this stage of design are to minimize construction costs and the potential for claims; analyze management and administration; satisfy stakeholder needs; and review the design, equipment, and materials used.5.3.4 During construction, analyze value analysis change proposals (VACP)/value engineering change proposals (VECP) of the contractor.6 VACPs/VECPs reduce the cost or duration of construction or present alternative methods of construction, without reducing performance or acceptance. To encourage the contractor to propose worthwhile VACPs/VECPs, the owner and the contractor share the resultant savings when permitted by contract.5.4 Products: 5.4.1 Perform VE/VA during concept development to provide a mechanism to analyze the essential attributes and develop possible alternatives to offer the best value. Evaluate technical requirements of each alternative to determine effects on total performance and costs. Identify areas of high cost/high-cost sensitivity and examine associated requirements in relation to its contribution to effectiveness. Utilize VE/VA to constructively challenge the stated needs and recommend alternatives and ensure that user requirements are well founded.5.4.2 Perform VE/VA during preliminary design to analyze the relevance of each requirement and the specifications derived from it. Critically examine the cost consequences of requirements and specifications to determine whether the resultant cost is comparable to the worth gained. Further analyze high-cost, low performance or high risk functions and the identification of alternative ways of improving value.5.4.3 Perform VE/VA during detail design to identify individual high-cost, low performance, or high risk areas to facilitate early detection of unnecessary costs in time to take corrective action. Establish maintenance plans to ensure that the design process incorporates logistic requirements and cost considerations, including reliability, maintainability, spares, and obsolescence. Analyze how suppliers can help reduce costs. Look for opportunities to simplify the design for operational use—make the product easier to operate and maintain.5.4.4 Perform VE/VA during production to develop alternative designs to meet functional needs. Apply VE/VA to evaluate and improve manufacturing processes, methods, and materials. Leverage opportunities for VE/VA when: recent developments indicate a potential opportunity for performance improvement or cost reduction, or both; the future use of the product depends on significant reduction in production costs; and new manufacturing technology or new materials become available.5.4.5 Perform VE/VA during operations to study the operation, maintenance, and other logistics functions.5.4.6 Encourage the contractor to propose worthwhile VACPs/VECPs that satisfy owner needs, where the owner and the contractor share the resultant savings when permitted by contract.5.5 Processes: 5.5.1 Perform VE/VA during process design to analyze the value of each requirement and the process steps derived from it. Critically examine the cost consequences of requirements to determine whether the resultant cost is comparable to the performance gained. Further analyze high-cost functions and the identification of alternative ways of achieving the same result with greater value (better performance, lower cost, or both).5.5.2 Perform VE/VA during process implementation. VE/VA challenges the need for data collection and test and use cases. VE/VA supports the testing process by challenging the amount of fidelity needed and determining cost effective ways of conducting tests. Look for opportunities to simplify the process design for operational use.5.5.3 Perform VE/VA during process operations. Apply VE/VA to evaluate and improve process flow, increase process throughput, and eliminate process bottlenecks. Leverage opportunities for VE/VA when: recent organizational changes indicate a potential opportunity for value improvement; initial incentives for process improvement or reduced cost, or both are no longer applicable; and new technology to improve productivity become available.5.5.4 Encourage the contractor to propose worthwhile VACPs/VECPs that satisfy owner needs, where the owner and the contractor share the resultant savings when permitted by contract.5.6 The number and timing of VE/VA studies varies for every focus of study. The owner/user/stakeholder, the design professional, and the value methodology expert determine the best approach jointly. A complex or expensive focus of study, or a design that will be used repeatedly, warrants a minimum of two VE/VA studies, performed before the design is developed and during design development.1.1 This practice covers a procedure for defining and satisfying the functions of a project, product, or process (hereafter referred to as focus of study). Projects include construction of commercial and residential buildings and other engineered systems.2 Products include components, systems and equipment.3 Processes include procurement, materials management, work flow, fabrication and assembly, quality control, and services.1.2 A multidisciplinary team uses the procedure to convert stakeholder constraints, needs, and desires into descriptions of functions and then relates these functions to resources.1.3 Examples of costs are all relevant costs over a designated study period, including the costs of obtaining funds, designing, purchasing/leasing, constructing/manufacturing/installing, operating, maintaining, repairing, replacing and disposing of the particular focus of study. While not the only criteria, cost is an important basis for comparison in a VE/VA study. Therefore, accurate and comprehensive cost data is an important element of the analysis.1.4 This is a procedure to develop alternatives that meet the functions of the focus of study. Estimate the costs for each alternative. Provide the owner/user/stakeholder with specific, technically accurate alternatives which can be implemented. The owner/user/stakeholder selects the alternative(s) that best satisfies their constraints, needs and desires.1.5 Apply this practice to an entire focus of study, or to any subsystem/element thereof. The user/owner/stakeholder can utilize the VE/VA procedure to select the element or scope of the study.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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